Need help finding a Good Book for my wife

My wife's birthday is approaching soon, and I'd like to get her a book that would really stimulate her mind, as she spends a lot of time working on the computer. She's into like, metaphysics in a way~ she totally went for 'the secret' and 'what the bleep do we know' before I discussed with her what was wrong with them.. and I think she still holds on to those kind of things. she's by no means like me, she's very much about what is not known or knowable than what is. SO, does anyone out there have experience with books about that kind of stuff? I would like to get her something she would appreciate, not something that I would like her to read. Books on metaphyics but that tie in secularism... just nothing too far off of the deep end would be nice. If there is anything out there that isn't Woo, just more spiritual than 'non spirituality' I would greatly appreciate being informed.